Apparatus, method and system to temporarily hold a workpiece during manufacturing using adhesive attachment

ABSTRACT

A method and system temporarily holds a workpiece, most suitably an aero engine turbine blade element during manufacture. The workholding system includes a support body with a contoured body surface, complementary to a workpiece surface, formed of a transparent material to define a bonding zone. The support body is supported by a base to form a workpiece shuttle, and a bond station receives the workpiece shuttle. Complementary zero-point locating elements on the shuttle and station assure accurate positioning. The bond station further has workpiece locating elements configured to accurately position the workpiece on the shuttle in a predetermined position relative to the zero-point locating elements of the shuttle, thereby compensating for shuttle-to-shuttle variance. An adhesive, such as a UV curable adhesive, is applied to the bonding zone and cured by UV through the transparent material, thereby fixing the workpiece in the predetermined position.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No.63/175,633 filed Apr. 16, 2021, the disclosure of which is herebyincorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to workholding of parts duringmanufacturing processes and, more specifically, to holding a turbineblade element by adhesive attachment of a contoured surface of theturbine blade element to a complementary contoured surface of a supportbody.

BACKGROUND OF THE INVENTION

Turbine blades are workpieces that are machined using a material removalprocess consisting of grinding, milling, EDM/ECM or by other means. Thecurrent state of the art uses a plurality of methods to hold the bladesduring manufacture including low melt alloy encapsulation, and hardpoint fixtures. When securing turbine blades to the workholding device,current state of the art workholding suffers from inefficiencies andhealth related problems due to the use of heavy metals and acids toremove them, small surface areas for adhesion and workpiece distortion.

Low melt alloys are used to secure a workpiece to a shuttle bysurrounding the workpiece with an alloy; this is referred to asencapsulation. To encapsulate a part, it is first located in a mold onthe part locating datums, referred to as a datum locating nest. Once thepart is loaded, the mold is closed and molten alloy is injected into themold thereby forming a secondary datum locating scheme relative to thepart datum set. The hot alloy can cause undesirable distortion of theshape of the blade by introducing thermal stresses into the bladematerial. After the alloy has cooled the mold is opened and the part,now surrounded by a metal matrix, is removed. Once the workpiece isprocessed and the encapsulation is no longer needed, the material isremoved by splitting it in half to release the part. A portion of thealloy is remelted and reused. Encapsulation is both costly and anenvironmental concern due to the cost of the raw material and wastedisposal. The workpiece must go through an acid bath to remove anyremaining allow stuck to the turbine blade as the alloy will create hotspots on the turbine blade during operation causing premature failure.The low melt alloys are toxic, expensive, and can subject a worker toinjury due to the heat required to melt the alloy.

Turbine blades are thin and compliant to reduce weight in an aircraftengine. These compliant blades are easily distorted due to their thincross sections. When a turbine blade is clamped into a fixture against apredetermined locating nest defined by the part datums, the part isoften distorted due to the clamping pressure which must be sufficient toprevent the part from moving during processing but weak enough to notdamage the blade. During the manufacturing process of the raw investmentcast turbine blades, individual differences arise within the blade shapethat can cause the blades to load differently within the hard pointtooling, further adding to part distortion.

Of secondary concern to hazardous materials and part distortion, thereis a need to access the part features required to perform an operation.Hard fixtures accommodate this need to grind multiple surfaces by theuse of multiple fixtures, repositioning the part as needed. But, sendinga part through different fixtures adds error to the final product andalso increases the risk of generating a bad part by improper partloading of the fixture.

FIG. 1 is a drawing from U.S. Pat. No. 8,341,841, illustrating a priorart approach to holding a workpiece. This drawing shows a componentcarrier 10 having a component body 12 and a composite material (shown inblack) located on a component receptacle 14. The composite material is awoven or non-woven material and an adhesive. This design requires ananti-shrinkage component to be place between the workpiece and thecarrier to prevent the workpiece from moving during the adhesive curingprocess. This method also requires the workpiece position to be measuredbefore processing, causing increased cost and cycle time. This designdoes not allow for the complete machining of the workpiece in onefixturing and relies on each carrier to be identical, which isimpractical and difficult to maintain in a production environment. Thevariation among the various carriers causes part variation and aninconsistent product.

FIG. 2 is a drawing from U.S. Pat. No. 10,227,874, illustrating anotherprior art approach to holding a workpiece. This drawing shows a toolingfixture assembly to hold a turbine blade 70. A transfer block 152 isattached to an end of the turbine blade using an ultraviolet-curedadhesive. Because the block 152 and blade 70 are opaque, curing onlyoccurs at a perimeter edge where the blade meets the block. The block152, with attached blade, is then positioned into a machining tool forprocessing.

FIG. 3 is a drawing from U.S. Pat. No. 9,272,379, illustrating yetanother prior art approach to holding a workpiece. This drawing shows amethod to hold a component using an adhesive. A component carrier 2 hasadapters 16 and 18 formed of a transparent material. The adapters allowUV curing of the adhesive in the area of the adapters. This method issimilar to U.S. Pat. No. 7,172,676 to DeMeter. This design relies ondisposable adapters and only attaches the workpiece in discrete areasdefined by the disposable adapters. The workpiece must be of asufficient size to provide an adequate surface area to bond to in orderto resist cutting forces without de-bonding the workpiece during theprocess of machining. Supporting the workpiece close to the machiningarea is difficult with this design. This method also increases cost dueto the wasted disposable adapters required to practice the method.

There remains a need for an improved apparatus, methods and systems fortemporarily holding a workpiece during manufacturing using adhesiveattachment.

SUMMARY OF THE INVENTION

The present invention provides a workholding system and a method fortemporarily holding a workpiece during one or more machining operationsusing adhesive attachment. In an example, the system and method are forholding a turbine blade element having a central blade portion and atleast one end portion for attaching the turbine blade element to aturbine assembly. The turbine blade element may have an airfoil shape.An exemplary workholding system includes a workpiece shuttle that holdsthe workpiece and is moved with the workpiece between one or moremanufacturing workstations. Typically, the workpiece has a contouredsurface that may be adhesively attached to the shuttle. The workpieceshuttle has a support body with a contoured body surface complementaryto the contoured surface of the workpiece. In examples, some or all ofthe contoured body surface of the support body is formed of atransparent material. The workpiece shuttle further has a base that isattached to and supports the support body so as to form the shuttle. Inan example, the base has a plurality of zero-point locating elements forlocating the base in a known position relative to a manufacturingworkstation to allow for precision machining.

A bond station is configured to receive the shuttle, and has a pluralityof zero-point locating elements that are complementary to the zero-pointlocating elements of the base of the shuttle. The shuttle is received onthe bond station and is positioned in a predefined position by thecomplementary zero-point elements of the base and bond station. Theworkpiece, such as a turbine blade element is positioned on the shuttlein a predetermined position relative to the zero-point locating elementsof the base. In an example, the bond station has a plurality ofworkpiece locating elements. In this example, the shuttle is in apredefined position relative to the bond station and the workpiecelocating elements enable positioning of the workpiece on the shuttle onthe predetermined position relative to the zero-point locating elements.As such, when the shuttle is positioned in a manufacturing workstation,using the zero-point locating elements, the workpiece is in a knownposition relative thereto and precision machining may occur. Clamps, notshown, may secure the workpiece during bonding.

A bonding zone is defined between the complementary portions of theworkpiece and support body. In examples, the bonding zone may be at theportion formed of transparent material. In certain versions, the entirecontoured body surface of the support body is formed of transparentmaterial and the bonding zone is the entire area of the complementarysurfaces. The contoured body surface of the support body may be largerthan the contoured surface of the workpiece, in which case the bondingzone would be where the contoured surfaces are coextensive. An adhesiveis applied to the bonding zone, such as being applied prior topositioning of the workpiece. The adhesive is then cured to temporarilyfix the workpiece in the predetermined position relative to thezero-point locating elements of the shuttle base. In examples, theadhesive is UV curable and the curing is accomplished by illuminatingthe bonding zone through the transparent material. In examples, thisprovides a very large area of attachment, which reduces the load betweenany given point of the workpiece and the support; the loads are spreadout of the large area.

The shuttle and workpiece may then be moved to one or more manufacturingworkstations for one or more manufacturing processes. The turbine bladeelement may then be debonded from the shuttle. In an example, thedebonding is accomplished using hot water or hot air. A ejection pin orelement may also be provided, such as in the support body, and movementof the pin or element may bias the workpiece away from the shuttle.Another advantageous embodiment has a resistive load positioned oppositethe adhesive side of the transparent material to thermal soften theworkholding adhesive when a current is applied for efficient removal ofthe turbine blade element from the transparent material. Anotherembodiment uses an adhesive that contains nanoscintillators to cure anadhesive by the use of an energy discharge device. Another embodimentuses nano components within the adhesive to trigger a curing event bythermal or chemical reaction. This reaction may be triggered bymagnetic, electronic, or other means. Another embodiment has aconductive substance mixed into the workholding adhesive to allow forinduction heating of the adhesive to thermally soften the adhesive forworkpiece removal from the shuttle.

In an embodiment, a method is provided for temporarily holding aworkpiece during one or more manufacturing processes, the workpiecehaving a contoured surface. The method includes providing a workholdingsystem having: a support body having a contoured body surfacecomplementary to the contoured surface of the workpiece, at least aportion of the complementary portion of the contoured body surfaceformed of a transparent material, the at least a portion that is formedof transparent material defining a bonding zone; a base attached to andsupporting the support body so as to form a workpiece shuttle, the basehaving a plurality of zero-point locating elements configured to locatethe base relative to a manufacturing workstation; a bond stationconfigured to receive the workpiece shuttle, the bond station having aplurality of zero-point locating elements complementary to thezero-point locating elements of the base. The method further includesthe steps of: receiving the workpiece shuttle on the bond station;positioning the workpiece shuttle in a predefined position by thecomplementary zero-point locating elements of the base of the workpieceshuttle and the bond station; receiving the workpiece on the supportbody with the contoured surface of the workpiece adjacent the bondingzone; positioning the workpiece on the workpiece shuttle in apredetermined position relative to the zero-point locating elements ofthe base of the shuttle; applying a workholding adhesive to the bondingzone between the contoured surface of the workpiece and thecomplementary contoured body surface of the support body; curing theadhesive such that the workpiece is temporarily fixed in thepredetermined position relative to the zero-point locating elements ofthe base of the workpiece shuttle; removing the workpiece shuttle, withthe workpiece affixed thereto, from the bond station and moving theworkpiece shuttle and workpiece to a first manufacturing workstation;performing at least one manufacturing process; and debonding theworkpiece from the shuttle.

In examples, the bond station further includes a plurality of workpiecelocating elements, and the step of positioning the workpiece on theworkpiece shuttle includes positioning the workpiece on the workpieceshuttle in the predetermined position relative to the zero-pointlocating elements of the base of the workpiece shuttle by the pluralityof workpiece locating elements of the bond station.

In examples, the support body includes two gripping devices each havinga contoured body surface complementary to a portion of the contouredsurface of the workpiece, each of the gripping devices having at least aportion of their contoured body surface formed of the transparentmaterial, the at least a portion that is formed of transparent materialof each of the gripping devices together defining the bonding zone. Thetwo gripping devices may be spaced apart.

In examples, each of the gripping devices is formed of the transparentmaterial or the support body is formed of the transparent material.

In examples, the workholding adhesive is a UV curable workholdingadhesive, and the step of curing the adhesive includes illuminating theadhesive in the bonding zone through the transparent material, therebycuring the adhesive.

In examples, the step of illuminating the adhesive includes: providing aUV curing station having a UV light source; disposing the bond station,with the workpiece shuttle and workpiece thereon, in the UV curingstation; and illuminating the adhesive using the UV curing station. TheUV curing station may include a UV conveyor having a UV light source anda conveying element, and the step of disposing the bond station, withthe workpiece shuttle and workpiece thereon, in the UV curing stationincludes: disposing the bond station, with the workpiece shuttle andworkpiece thereon, on the conveying element; and moving the bondstation, with the workpiece shuttle and workpiece thereon, relative tothe UV light source by the conveying element. The conveying element maybe disposed above the UV light source such that the conveying elementmoves the bond station over the UV light source and UV light from the UVlight sources passes upwardly through one or more openings in theworkpiece shuttle and bond station so as to illuminate the bonding zone.

In examples, the step of illuminating the adhesive includes providing aUV light source disposed in the workpiece shuttle and illuminating theadhesive using the UV light source. The gripping devices may each have apocket and the UV light source may be a UV light source received in eachpocket. The UV light source may be connected to a power source outsidethe workpiece shuttle by electrical connectors or the UV light sourcemay be self-contained and includes a power source, the UV light sourcesbeing in wireless communication with a control.

In examples, the support body is formed entirely of the transparentmaterial the workpiece shuttle further includes a UV light sourcedisposed in or adjacent to the transparent material and configured toilluminate the bonding zone.

In examples, the workpiece is a turbine blade element having a centralblade portion and at least one end portion, the central blade portionhaving a contoured blade surface defining the contoured surface of theworkpiece.

In examples, the workpiece shuttle may further include an upper portionwith second support body, the second support body having a contouredbody surface complementary to an additional contoured surface of theworkpiece, an additional bonding zone defined where the contoured bodysurface of the second support body is coextensive with the additionalcontoured surface of the workpiece, and the method may further includemoving the upper portion of the workpiece shuttle from an open positionto a closed position wherein the contoured body surface of the secondsupport body is adjacent the additional contoured surface of theworkpiece.

In examples, the method further includes applying the adhesive to theadditional bonding zone, and the curing step includes curing theadhesive in both bonding zones.

In examples, at least a portion of the contoured body surface of thesecond support body is formed of a transparent material, or the secondsupport body is formed of the transparent material.

In another embodiment, a workholding system is provided for temporarilyholding a workpiece during one or more manufacturing processes, theworkpiece having a contoured surface. The system includes: a supportbody having a contoured body surface complementary to the contouredsurface of the workpiece, at least a portion of the complementaryportion of the contoured body surface formed of a transparent material,the at least a portion that is formed of transparent material defining abonding zone; a base attached to and supporting the support body so asto form a workpiece shuttle, the base having a plurality of zero-pointlocating elements configured to locate the base relative to amanufacturing workstation; and a bond station configured to receive theworkpiece shuttle, the bond station having a plurality of zero-pointlocating elements complementary to the zero-point locating elements ofthe base, the bond station further having a plurality of workpiecelocating elements operable to locate the workpiece disposed on thesupport body of the workpiece shuttle when the workpiece shuttle isreceived by the bond station, the workpiece locating elementspositioning the workpiece on the workpiece shuttle in a predeterminedposition relative to the zero-point locating elements of the base of theworkpiece shuttle.

In examples, the support body includes two gripping devices each havinga contoured body surface complementary to a portion of the contouredsurface of the workpiece, each of the gripping devices having at least aportion of their contoured body surface formed of the transparentmaterial, the at least a portion that is formed of transparent materialof each of the gripping devices together defining the bonding zone. Thetwo gripping devices may be spaced apart.

In examples, each of the gripping devices is formed of the transparentmaterial or the support body is formed of the transparent material.

In examples, the temporary holding comprises an adhesive holding with aUV curable workholding adhesive. The system may further include a UVcuring station having a UV light source operable to illuminate and curethe adhesive.

In examples, the UV curing station includes a UV conveyor having a UVlight source and a conveying element, the conveying element beingdisposed above the UV light source such that the conveying element isoperable to move the bond station over the UV light source and UV lightfrom the UV light sources passes upwardly through one or more openingsin the workpiece shuttle and bond station so as to illuminate thebonding zone.

In examples, the system further includes a UV light source disposed inthe workpiece shuttle operable to illuminate the adhesive using the UVlight source. The gripping devices may each have a pocket and the UVlight source comprises a UV light source received in each pocket. The UVlight source may be connected to a power source outside the workpieceshuttle by electrical connectors or the UV light source may beself-contained and includes a power source, the UV light sources beingin wireless communication with a control.

In examples, the support body is formed entirely of the transparentmaterial and the workpiece shuttle further includes a UV light sourcedisposed in or adjacent to the transparent material and configured toilluminate the bonding zone.

In examples, the workpiece is a turbine blade element having a centralblade portion and at least one end portion, the central blade portionhaving a contoured blade surface defining the contoured surface of theworkpiece.

In examples, the workpiece shuttle further includes an upper portionwith second support body, the second support body having a contouredbody surface complementary to an additional contoured surface of theworkpiece, an additional bonding zone defined where the contoured bodysurface of the second support body is coextensive with the additionalcontoured surface of the workpiece, the upper portion of the workpieceshuttle being movable from an open position to a closed position whereinthe contoured body surface of the second support body is adjacent theadditional contoured surface of the workpiece. At least a portion of thecontoured body surface of the second support body may formed of atransparent material, or the second support body may be formed of thetransparent material.

In a further embodiment, a method is provided for temporarily holding aturbine blade element during one or more manufacturing processes, theturbine blade element having a central blade portion and at least oneend portion, the central blade portion having a contoured blade surface.The method includes providing a workholding system having: a supportbody having a contoured body surface complementary to the contouredblade surface, the complementary portion of the contoured body surfacedefining a bonding zone entirely formed of a transparent material; abase attached to and supporting the support body so as to form aworkpiece shuttle, the base having a plurality of zero-point locatingelements configured to locate the base relative to a manufacturingworkstation, the base further having a support face; and a bond stationconfigured to receive the shuttle, the bond station having a pluralityof zero-point locating elements complementary to the zero-point locatingelements of the base, the bond station further having a plurality ofworkpiece locating elements. The method includes the steps of: receivingthe shuttle on the bond station; positioning the shuttle in a predefinedposition by the complementary zero-point locating elements of the baseand bond station; receiving the turbine blade element on the supportbody with the contoured blade surface adjacent the bonding zone;positioning the turbine blade element on the shuttle in a predeterminedposition relative to the zero-point locating elements of the base of theshuttle by the plurality of workpiece locating elements of the bondstation; applying a UV curable workholding adhesive to the bonding zonebetween the contoured blade surface and the complementary body surface;illuminating the adhesive in the bonding zone through the transparentmaterial with UV, thereby curing the adhesive such that the turbineblade element is temporarily fixed in the predetermined positionrelative to the zero-point locating elements of the base of the shuttle;removing the shuttle, with the turbine blade element affixed thereto,from the bond station and moving the shuttle and turbine blade elementto a first manufacturing workstation; performing at least onemanufacturing process; and debonding the turbine blade element from theshuttle.

In examples, the step of illuminating the adhesive includes: providing aUV curing station having a UV light source; disposing the bond station,with the shuttle and turbine blade element thereon, in the UV curingstation; and illuminating the adhesive using the UV curing station.

In examples, the UV curing station includes a UV conveyor having a UVlight source and a conveying element, and the step of disposing the bondstation, with the shuttle and turbine blade element thereon, in the UVcuring station includes disposing the bond station, with the shuttle andturbine blade element thereon, on the conveying element and moving thebond station, with the shuttle and turbine blade element thereon,relative to the UV light source by the conveying element.

In examples, the conveying element is disposed above the UV light sourcesuch that the conveying element moves the bond station over the UV lightsource and UV light from the UV light source passes upwardly through oneor more openings in the shuttle and bond station so as to illuminate thebonding zone.

In examples, the support body is formed entirely of the transparentmaterial, and the workpiece shuttle further includes a UV light sourcedisposed in or adjacent to the transparent material and configured toilluminate the bonding zone.

In examples, the support body includes two gripping devices each havinga contoured body surface complementary to a portion of the contouredsurface of the workpiece, each of the gripping devices having at least aportion of their contoured body surface formed of the transparentmaterial, the at least a portion that is formed of transparent materialof each of the gripping devices together defining the bonding zone. Thetwo gripping devices may be spaced apart, and may be formed of thetransparent material.

In examples, the step of illuminating the adhesive includes providing aUV light source disposed in the workpiece shuttle and illuminating theadhesive using the UV light source. The gripping devices may each have apocket and the UV light source is a UV light source received in eachpocket.

In examples, the workpiece shuttle further includes an upper portionwith a second support body, the second support body having a contouredbody surface complementary to an additional contoured surface of theworkpiece, an additional bonding zone defined where the contoured bodysurface of the second support body is coextensive with the additionalcontoured surface of the workpiece, and the method further includesmoving the upper portion of the workpiece shuttle from an open positionto a closed position wherein the contoured body surface of the secondsupport body is adjacent the additional contoured surface of theworkpiece.

In examples, the method further includes applying the adhesive to theadditional bonding zone, the illuminating step comprising illuminatingthe adhesive in both bonding zones.

In examples, at least a portion of the contoured body surface of thesecond support body is formed of a transparent material or the secondsupport body is entirely formed of the transparent material.

In yet another embodiment, a method is provided for temporarily holdinga workpiece during one or more manufacturing processes, the workpiecehaving a contoured surface. The method includes providing a workholdingsystem having: a support body having a contoured body surfacecomplementary to the contoured surface of the workpiece, at least aportion of the complementary portion of the contoured body surfaceformed of a transparent material, the at least a portion that is formedof transparent material defining a bonding zone; a base attached to andsupporting the support body so as to form a workpiece shuttle, the basehaving a plurality of zero-point locating elements configured to locatethe base relative to a manufacturing workstation, the base furtherhaving a support face; and a bond station configured to receive theshuttle, the bond station having a plurality of zero-point locatingelements complementary to the zero-point locating elements of the base,the bond station further having a plurality of workpiece locatingelements. The method includes the steps of: receiving the shuttle on thebond station; positioning the shuttle in a predefined position by thecomplementary zero-point locating elements of the base and bond station;receiving the workpiece on the support body with the contoured surfaceadjacent the bonding zone; positioning the workpiece on the shuttle in apredetermined position relative to the zero-point locating elements ofthe base of the shuttle by the plurality of workpiece locating elementsof the bond station; applying a UV curable workholding adhesive to thebonding zone between the contoured surface of the workpiece and thecomplementary body surface; illuminating the adhesive in the bondingzone through the transparent material with UV, thereby curing theadhesive such that the workpiece is temporarily fixed in thepredetermined position relative to the zero-point locating elements ofthe base of the shuttle; removing the shuttle, with the workpieceaffixed thereto, from the bond station and moving the shuttle andworkpiece to a first manufacturing workstation; performing at least onemanufacturing process; and debonding the workpiece from the shuttle.

In examples, the workpiece shuttle further includes an upper portionwith a second support body, the second support body having a contouredbody surface complementary to an additional contoured surface of theworkpiece, an additional bonding zone defined where the contoured bodysurface of the second support body is coextensive with the additionalcontoured surface of the workpiece, and the method further includesmoving the upper portion of the workpiece shuttle from an open positionto a closed position wherein the contoured body surface of the secondsupport body is adjacent the additional contoured surface of theworkpiece. The step of applying adhesive includes applying adhesive toboth bonding zones and the step of illuminating includes illuminatingthe adhesive in both bonding zones with UV.

In examples, the step of illuminating the adhesive includes: providing aUV curing station having a UV light source, the UV curing station havinga UV light source and a conveying element, the conveying elementdisposed above the UV light source such that the conveying element movesthe bond station over the UV light source; disposing the bond station,with the workpiece shuttle and workpiece thereon, in the UV curingstation; and illuminating the adhesive using the UV curing station, theUV light from the UV light source passing upwardly through one or moreopenings in the workpiece shuttle and bond station so as to illuminatethe bonding zone.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a prior art adhesive fixture;

FIG. 2 is a perspective view of a prior art workpiece locating system;

FIG. 3 is a cross sectional side view of another prior art approach toproviding an adhesive fixture;

FIG. 4 is an exploded perspective view of an embodiment of a workholdingsystem according to the present invention;

FIG. 5 is a perspective view similar to FIG. 4 but with the workpieceshuttle received in the bond station;

FIG. 6 is a perspective view similar to FIG. 5 but with the turbineblade element located on the shuttle in the bond station;

FIG. 7 is an exploded side perspective view of a turbine blade element,shuttle and bond station according to another embodiment of the presentinvention;

FIG. 8 is a top view of the workholding system of FIG. 7 ;

FIG. 9 is a cross sectional view of the workholding system of FIG. 8taken along lines A-A;

FIG. 10 is a top perspective view of the workpiece shuttle and blade ofthe system of FIGS. 7-9 ;

FIG. 11 is a bottom perspective view of the workpiece shuttle and bladeof FIG. 10 ;

FIG. 12 is a top perspective view of the bond station of the system ofFIGS. 7-9 configured to receive the workpiece shuttle of FIGS. 10 and 11;

FIG. 13 is a bottom perspective view of the bond station of FIG. 12 ;

FIG. 14 is a side view of an alternative embodiment of a workpieceshuttle received into the bond station of FIGS. 12 and 13 , to form aworkholding system;

FIG. 15 is a perspective view of the workpiece shuttle and bond stationof FIG. 14 ;

FIG. 16 is a cross sectional side view of the workpiece shuttle of FIGS.14 and 15 without the bond station;

FIG. 17 is a perspective view of the workpiece shuttle of FIG. 16 ;

FIG. 18 is a top perspective view of the workpiece shuttle of FIGS. 10and 11 received into the bond station of FIGS. 12 and 13 , to form aworkholding system;

FIG. 19 is a bottom perspective view of the workholding system of FIG.18 ;

FIG. 20 is a side perspective view of the workholding system of FIGS. 18and 19 ;

FIG. 21 is a bottom view of the workholding system of FIGS. 18-20 ;

FIG. 22 is a cross sectional view of an embodiment of a shuttle showingan ejector device for de-bonding a part from a fixture, which may form aportion of some embodiments of the present invention;

FIG. 23 is a cross section view similar to FIG. 22 but showing anembodiment of an ultraviolet generating device encapsulated into atransparent material, which may form a portion of some embodiments ofthe present invention;

FIG. 24 is a cross section view similar to FIG. 22 but showing anembodiment of an encapsulant material inside of a workpiece supportmaterial which contains a radio frequency device to heat an adhesive,which may form a portion of some embodiments of the present invention;

FIG. 25 is a schematic view showing how a light source may be insertedparallel into an optically transparent material forming part of aworkpiece shuttle in certain embodiments;

FIG. 26 is a schematic view showing how a light source may be insertedlaterally into a transparent material forming part of a workpieceshuttle in certain embodiments;

FIG. 27 is a cross sectional view showing a flexible light sourceconforming to the underside of a transparent material forming part of aworkpiece shuttle in certain embodiments;

FIG. 28 is a perspective view of an alternative embodiment of atransparent component that contains integral locating areas;

FIG. 29 is a perspective view of an alternative embodiment of a portionof a workpiece shuttle with a turbine blade element spanning twotransparent locating components of FIG. 28 ;

FIG. 30 is a perspective view of an alternative embodiment of a portionof a workpiece shuttle with a turbine blade element similar to FIG. 29but with a tie-bar spanning two transparent locating components;

FIG. 31 is a side view of the transparent component showing anultraviolet light source being inserted into the transparent component.

FIG. 32 is a perspective view of an alternative embodiment of aworkpiece support portion of a workpiece shuttle that may be anadditively printed metallic housing with slots to accept a pourable orinjectable transparent material;

FIG. 33 is a side view of the portion of FIG. 32 showing insertion of anultraviolet light source;

FIG. 34 is a perspective view of an embodiment of an adhesive bondstation receiving a workpiece shuttle and workpiece, wherein theworkpiece shuttle has individual locating components held together by atie-bar apparatus, and also having a positioning device to align thesystem;

FIG. 35 is a perspective view showing a robot positioning a workpieceonto a shuttle;

FIG. 36 is a perspective view depicting a 6th axis axis support for aworkpiece shuttle;

FIG. 37 is a perspective view showing a conveyor for curing anultraviolet workholding adhesive;

FIG. 38 is a schematic perspective view showing workpieces on workpieceholding systems going into an ultraviolet workholding adhesive curingconveyor and shuttles with workpieces being separated from the bondstations after exiting the conveyor;

FIG. 39 is a cross sectional view of an embodiment of a conveyor;

FIG. 40 is a top view of portions of the conveyor of FIG. 39 ;

FIG. 41 is a schematic view of a system for machining a support body foruse with certain embodiments of the present invention; and

FIG. 42 is a flowchart for an exemplary set of steps according to anembodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a workholding system and a method fortemporarily holding a workpiece during one or more machining operationsusing adhesive attachment. In an example, the system and method are forholding a turbine blade element having a central blade portion and atleast one end portion for attaching the turbine blade element to aturbine assembly. The turbine blade element may have an airfoil shape.An exemplary workholding system includes a workpiece shuttle that holdsthe workpiece and is moved with the workpiece between one or moremanufacturing workstations. Typically, the workpiece has a contouredsurface that may be adhesively attached to the shuttle. The workpieceshuttle has a support body with a contoured body surface complementaryto the contoured surface of the workpiece. In examples, some or all ofthe contoured body surface of the support body is formed of atransparent material. The workpiece shuttle further has a base that isattached to and supports the support body so as to form the shuttle. Inan example, the base has a plurality of zero-point locating elements forlocating the base in a known position relative to a manufacturingworkstation to allow for precision machining.

A bond station is configured to receive the shuttle, and has a pluralityof zero-point locating elements that are complementary to the zero-pointlocating elements of the base of the shuttle. The shuttle is received onthe bond station and is positioned in a predefined position by thecomplementary zero-point elements of the base and bond station. Theworkpiece, such as a turbine blade element is positioned on the shuttlein a predetermined position relative to the zero-point locating elementsof the base. In an example, the bond station has a plurality ofworkpiece locating elements. In this example, the shuttle is in apredefined position relative to the bond station and the workpiecelocating elements enable positioning of the workpiece on the shuttle onthe predetermined position relative to the zero-point locating elements.As such, when the shuttle is positioned in a manufacturing workstation,using the zero-point locating elements, the workpiece is in a knownposition relative thereto and precision machining may occur. Clamps, notshown, may secure the workpiece during bonding.

A bonding zone is defined between the complementary portions of theworkpiece and support body. In examples, the bonding zone may be at theportion formed of transparent material. In certain versions, the entirecontoured body surface of the support body is formed of transparentmaterial and the bonding zone is the entire area of the complementarysurfaces. The contoured body surface of the support body may be largerthan the contoured surface of the workpiece, in which case the bondingzone would be where the contoured surfaces are coextensive. An adhesiveis applied to the bonding zone, such as being applied prior topositioning of the workpiece. The adhesive is then cured to temporarilyfix the workpiece in the predetermined position relative to thezero-point locating elements of the shuttle base. In examples, theadhesive is UV curable and the curing is accomplished by illuminatingthe bonding zone through the transparent material. In examples, thisprovides a very large area of attachment, which reduces the load betweenany given point of the workpiece and the support; the loads are spreadout of the large area.

The shuttle and workpiece may then be moved to one or more manufacturingworkstations for one or more manufacturing processes. The turbine bladeelement may then be debonded from the shuttle. In an example, thedebonding is accomplished using hot water or hot air. A ejection pin orelement may also be provided, such as in the support body, and movementof the pin or element may bias the workpiece away from the shuttle.Another advantageous embodiment has a resistive load positioned oppositethe adhesive side of the transparent material to thermal soften theworkholding adhesive when a current is applied for efficient removal ofthe turbine blade element from the transparent material. Anotherembodiment uses an adhesive that contains nanoscintillators to cure anadhesive by the use of an energy discharge device. Another embodimentuses nano components within the adhesive to trigger a curing event bythermal or chemical reaction. This reaction may be triggered bymagnetic, electronic, or other means. Another embodiment has aconductive substance mixed into the workholding adhesive to allow forinduction heating of the adhesive to thermally soften the adhesive forworkpiece removal from the shuttle.

Specific embodiments of the present invention will now be described. Itshould be understood that the invention is not limited to these specificembodiments. Also, any feature or element discussed with any embodimentmay be used with any other embodiment, as will be clear to those ofskill in the art.

Referring now to FIG. 4 , an exemplary workholding system 200 includes ashuttle 210 and a bond station 230. The workpiece 202, which in thisexample is a turbine blade element, may be considered part of thesystem, or the system may be separate from the workpiece. In use, theshuttle 210 is received on the bond station 230 as shown in FIG. 5 andthe workpiece 202 is received on the shuttle 210 as shown in FIG. 6 .The above described steps may then be carried out.

The details of an embodiment of an exemplary workholding system will bedescribed in more detail with respect to FIGS. 7-17 . Like numbers areused for like-named parts throughout the specification for consistency,but do not require that all like-numbered parts are identical.

FIG. 7 provides an exploded side perspective view of a workpiece orturbine blade element 202, workpiece shuttle 210 and bond station 230according to an embodiment of the present invention. FIG. 8 provides atop view of the workholding system of FIG. 7 with the turbine bladeelement 202 and shuttle 210 received in the bond station 230. FIG. 9provides a cross sectional view of the workholding system of FIG. 8taken along lines A-A.

In this example, the turbine blade element 202 has a central bladeportion 204 extending between a pair of end portions 207 definingopposed ends of the turbine blade element. In this example, the endportions 207 enable the turbine blade element 202 to be assembled to alarger turbine structure. In this example, the central blade portion 204may be said to have a top face 205 and a bottom face 206, with termssuch as top and bottom being in reference to the drawings but not beinglimiting on the structure. In this example, the bottom face 206 alsodefines a contoured blade surface 204 for attaching the turbine bladeelement to the shuttle. As used herein, a contoured surface means anon-flat surface, which may have a complex geometry.

Referring now to FIGS. 7-11 , the workpiece shuttle 210 will bedescribed in more detail. FIG. 10 provides a top perspective view of theworkpiece shuttle and turbine blade element of the system of FIGS. 7-9 .FIG. 11 provides a bottom perspective view of the workpiece shuttle andturbine blade element of FIG. 10 . In this example, the workpieceshuttle 210 has a support body 212 on its upper face. The support body212 has a contoured body surface 214 that is shaped so as to becomplementary to the contoured blade surface 204. As used herein,complementary is defined as the shape fitting closely with the othershape. The support body may be unique to a given workpiece shape, suchthat different parts are held by different workpiece shuttles or supportbodies. In this example, a bonding zone is defined as the area where thecomplementary surfaces are coextensive. The contoured body surface 214of the support body 212 may be somewhat smaller than the entire bottomface 206 of the central blade portion 203 to avoid touching orinterfering with the end portions 207. In further examples, the bondingzone may be one or more areas within the area where the complementarysurfaces are coextensive. In certain embodiments, the entirety of thecontoured body surface 214 is formed of a transparent material. In someembodiments, the entirety of the support body 212 is formed of atransparent material; the support body is a monolithic body oftransparent material. A variety of transparent materials may be used,with sapphire being one useful example as it has a hard surface and isdimensionally stable. In certain further embodiments, only a portion ofthe support body 212 or contoured body surface 214 is formed of atransparent material. For example, only the bonding zone may be formedof transparent material or only an upper portion of the support body maybe formed of transparent material.

The workpiece shuttle 210 further has a base 218 that is attached to andsupports the support body 212. For example, they may be adhesivelyconnected, brazed and/or mechanically interconnected. The base 218, inthis example, has an upper face 219 and a lower face 220, with thesupport body 212 being disposed on the upper face 219.

The present invention seeks to provide precise locating of a workpiece,such as the turbine blade element 202, in various manufacturingprocesses. As known to those of skill in the art, a zero-point locatingsystem is a system of complementary locating elements used on fixturesand manufacturing workstations for repeatedly and accurately positioninga workpiece without the need for taking additional measurement orperforming position checks. As used herein, a zero-point locating systemis any system that allows precise positioning of a workpiece shuttlerelative to the bond station and to manufacturing workstations, withoutthe need for taking additional measurement or performing positionchecks, whether or not such a system is commonly referred to as azero-point locating system. Such systems may also include clampingelements for clamping the elements relative to each other.

In this example, the workpiece shuttle 210 has a first locating element221 extending from the lower face 220 of the base 218 and a secondlocating element 222, in the form of a recess, defined in the lower face220. As used herein, locating elements may be any physical feature thatprovides for precise locating.

Referring now to FIGS. 7 and 12-13 , the bond station 230 will bedescribed in more detail. FIG. 7 was briefly described above. FIG. 12provides a top perspective view of the bond station 230, which isconfigured to receive the workpiece shuttle 210 of FIGS. 10 and 11 .FIG. 13 provides a bottom perspective view of the bond station 230.

The bond station 230 has zero-point locating elements complementary tothe zero-point locating elements of the base of the workpiece shuttle.In this example, the bond station 230 has an upper face 231 and anopposed lower face 232. A first locating element 233 and a secondlocating element 234 are provided on the upper face. In this example,the first locating element 233 is a recess in the upper face 231complementary to the first locating element 221 extending from the lowerface 220 of the workpiece shuttle 210. In this example, the secondlocating element 234 is a spring loaded clocking pin that extendsupwardly from the upper face 231 and is complementary to the recess 222in the lower face of the workpiece shuttle 210.

In this example, the bond station also has an upper portion 236 having aplurality of workpiece locating elements. The workpiece locatingelements are physical elements shapes so as to precisely position theworkpiece 202 at a predetermined position. The workpiece locatingelements may take a variety of forms, depending on the configuration ofthe workpiece. In this example, the workpiece locating elements take theform of a first locating arm 237 and a second locating arm 238 eachextending from the upper portion 236 of the bond station 230 (see FIGS.12 and 13 ). Each of the locating arms have precise positioning featuresthat contact surfaces or features of the work piece such that when theworkpiece 202 engages these features, the workpiece is in a precisepredefined position relative to the bond station 230. As will be clearto one skilled in the art, a method to verify the locations of thelocating part and shuttle can be provide through various means includingnon-contact sensors, contact sensors, coordinate measuring machine or avision system.

FIGS. 7, 9 and 20-21 help to illustrate how the workpiece 202, workpieceshuttle 210 and bond station 230 work together. FIG. 18 provides a topperspective view of the workpiece shuttle of FIGS. 10 and 11 receivedinto the bond station of FIGS. 12 and 13 , to form a workholding system.FIG. 19 provides a bottom perspective view of the workholding system ofFIG. 18 . FIG. 20 provides a side perspective view and FIG. 21 providesa bottom view of the workholding system of FIGS. 18-21 . As best shownin FIGS. 7 and 9 , the workpiece shuttle 210 is received onto the bondstation 230 with the upper face 231 of the bond station contacting,supporting, and being coplanar with the lower face 232 of the base 218of the workpiece shuttle. The first locating element 221 of theworkpiece shuttle 210 is received into the complementary first locatingelement 233 of the bond station 230. Likewise, the second locatingelement, or recess, 222 of the workpiece shuttle 210 receives the secondlocating element 234 of the bond station 230. The faces 220 and 231 alsohelp to locate the workpiece shuttle relative to the bond station 230,by making contact and being coplanar, and therefore may also beconsidered as additional complementary locating elements. The workpieceshuttle is positioned in a predefined position by the complementarylocating elements.

With the workpiece shuttle 210 received by the bond station 230, theworkpiece 202 may now be positioned. As noted above, the bond station230 has workpiece locating elements for locating the workpiece in apredetermined position. Because the complementary locating elements ofthe workpiece shuttle 210 and bond station 230 cooperate to position theshuttle in a predetermined position, the workpiece locating elementsserve to locate the workpiece in a precise position relative to thelocating elements of the shuttle. The workpiece 202 is positioned in thepredetermined position, using the workpiece locating elements of thebond station. This also positions the contoured blade surface 204 of theturbine blade element 202 adjacent the contoured body surface 214 of thesupport body 212 of the workpiece shuttle. The workpiece locatingelements may be connected to an electrical circuit to provide feedbackfrom each locating element to verify the correct part and shuttlelocations. The zero-point locating elements may also provide feedback.The feedback signal may be wireless.

An adhesive is applied to the bonding zone between the complementarysurfaces of the workpiece 202 and the support body 212 and is cured. Theadhesive may be applied to one or both surfaces prior to positioning theworkpiece 202 on the workpiece locating elements of the bond station230. In an advantageous embodiment, adhesive is applied to the bondingzone using a robot or a computer-controlled machine requiring no humanintervention. The adhesive may be applied using a CNC machine tool usingthe machine driven axis to position a dispensing nozzle to the requiredposition to dispense adhesive to the shuttle. Once the adhesive iscured, the workpiece is fixed in a predetermined position relative tothe zero-point locating elements of the shuttle. The shuttle, with theworkpiece fixed thereto, may then be removed from the bond station andmoved to one or more manufacturing workstations. Each workstation willhave locating elements that cooperate with the locating elements of theshuttle, thereby positioning the workpiece in a known position. Inexamples, no position check or adjustment is required for machining.

FIGS. 14-17 illustrate an alternative embodiment of a workpiece shuttle.The workpiece shuttle is similar to the workpiece shuttle 210 butincludes additional elements. The common elements will not be furtherdescribed. FIG. 14 is a side view of the alternative embodiment of theworkpiece shuttle received into the bond station of FIGS. 12 and 13 , toform a workholding system. FIG. 15 is a perspective view of theworkpiece shuttle and bond station of FIG. 14 . FIG. 16 is a crosssectional side view of the workpiece shuttle of FIGS. 14 and 15 withoutthe bond station. FIG. 17 is a perspective view of the workpiece shuttleof FIG. 16 .

This alternative workpiece shuttle has an upper portion or clam shell215 that is pivotably connected to the remainder of the shuttle at pivot216. It may be said to move between an open position and a closedposition. The upper portion of clam shell 215 includes a second supportbody 213 that has a contoured body surface complementary to anadditional contoured surface of a workpiece. In this example, thecentral blade portion of the turbine blade element has a top face 205(see FIGS. 9 and 10 ) defining an additional contoured blade surface.The contoured body surface of the second support body 213 iscomplementary to this additional contoured body surface. After theturbine blade element is position on the support body, the upper portionor clam shell 215 may be moved from the open position to the closedposition such that the second support body 213 is adjacent theadditional contoured blade surface and may be adhesively attachedthereto. An additional bonding zone is defined where the complementarysurfaces are coextensive. The second support body may be partially orentirely formed of transparent material. Some or all of the contouredbody surface of the second support body may be formed of the transparentmaterial. A latch 211 may hold the upper portion or clam shell 215 inthe closed position. The method may further include moving the upperportion to the open position after debonding.

A benefit of embodiments as just described is that the bond stationlocates the workpiece in a predetermined position relative to thelocating elements of the shuttle, so part-to-part variation in theshuttles does not impact the precise positioning of the workpiece duringsubsequent machining operations. In an example, a single bond station isused with a plurality of shuttles, thereby requiring only the bondstation to be precisely dimensioned, and subject to calibration checks,instead of having to do the same with each of the plurality of shuttles.It is noted that the adjacent contoured surfaces 204, 214 of theworkpiece 202 and support body 212 may not be equidistant at all areas,due to variations in the workpiece shuttle 210. As an example, there maybe tiny variations in the contoured body surface 214. The adhesivethickness may vary slightly in different areas. However, because thebond station precisely locates the workpiece relative to the locatingelements of the workpiece shuttle, each workpiece is precisely locatedwith the adhesive thickness variation compensating for variations in theshuttles. Providing the workpiece locating elements and doing thelocating in the bond station, prior to machining, avoids exposing thehigh-precision bond station to machining forces and excess relocation.Only the shuttle is exposed to these forces and relocation, and the bondstation compensates for shuttle-to-shuttle variance.

In an alternative embodiment, the workpiece shuttle may includeworkpiece locating elements for locating the workpiece relative thereto.These workpiece locating elements may be in addition to or in place ofthe workpiece locating elements on the bond station. However, having theworkpiece locating elements on the bond station, and not on theworkpiece shuttle, is advantageous in some applications.

After the desired manufacturing processes are complete, the workpiece isde-bonded and removed from the workpiece shuttle. This may beaccomplished in a variety of ways. In certain versions, exposure to hotwater or hot air accomplishes the debonding. FIG. 22 illustrates anejector system that may assist in debonding. A portion of a workpieceshuttle is shown at 210, with a support body 212 supporting a workpiece202. An ejector 250 extends up through a passage 252 in the shuttlesupport body 212. The ejector 250 may upwardly and push against thebottom face of the workpiece, thereby urging the workpiece away from thesupport body. This ejector 250 may be an integral part of the shuttle orit may be in a separate device. The ejector is operated in a linearfashion to separate the workpiece from the shuttle, or it may be a fixedobject onto which the shuttle may be pressed.

The adhesive used to attach the workpiece to the support body may be ofany type suitable for adhesively attaching the workpiece. In certainadvantageous embodiments, the adhesive is an ultraviolet (UV) curableworkholding adhesive that cures when exposed to UV light. In certainadvantageous embodiments, this adhesive is debondable using hot air orhot water. In examples, the entire bonding zone is transparent and theentirety of the bonding zone is illuminated with UV through thetransparent support body or support body portion.

The UV illumination may be accomplished in a variety of ways. In anexample, as shown in FIG. 23 a UV light source 260 is embedded into thetransparent material forming the support body 260. The light source 260may have leads 262 that connect to pads 264 that allow for the operationof the light source 260 through external contacts with a power supply.For example, the bond station may have electrical contacts for poweringthe light source and for controlling the timing of the illumination. Itwill be noted that connections may include other functions such ashealth monitoring of the apparatus and process performance. Theencapsulation material 266 used to embed the light source 260 may be athermal heat sink material to draw heat away from the light source,typically an LED diode. The encapsulating material is also a sealingmaterial to prevent fluid ingress into the area of the light source andother electronics.

In an alternative, as shown in FIG. 24 , a non-optical device 270 may beinserted into a structural workholding support body 212 to cure anadhesive whether by thermal, induction coil, piezo, radio frequencydielectric or atomic excitation of the adhesive molecules. In thisalternative, the support body may or may not be partially or entirelytransparent. All such non-optical devices may be coupled to externalpower sources as shown in FIG. 23 . As a further alternative, a UV lightsource or non-optical device may have its own power supply, such as abattery, and therefore not require electrical connections. In oneexemplary embodiment of the invention, the UV LEDs are assembled into anassembly with a heat sink then mounted into the shuttle. Provided on theshuttle or LED assembly is a means to seal off the UV LEDs to externalcontamination such as an O-ring or adhesive sealant. The electricalcontacts are exposed to make an electrical connection with the LEDcontroller. Wireless power transmission, such as through inductivecoupling, may also be used to power the light or device. In each case,the light or device may be wirelessly controlled, so as to allow remotetriggering. As an example, wireless UV curing heads may include abattery, UV source, Bluetooth or other means of triggering andmonitoring the curing process from a distance, and a controller thatwould have a Bluetooth transmitter or other wireless protocol to triggerand monitor the curing process. The LED heads would handshake with aspecific controller by placing the LED head onto the controller to“register” the LED head so multiple controllers/LED heads could be usedin the same area. Optionally, a controller and LED heads could be taggedwith matching colors or other means to identify that they go together.Remote triggering may be advantageous in avoiding exposure of workers tothe energy sources. The energy released may be of a frequency orultrashort time duration to not affect the workpiece material in anegative way.

The UV or other energy device may be engaged with the shuttle in any ofa variety of ways. For example, the device may be part of the bondstation, with the shuttle having openings into which the devices fitwhen the shuttle is received in the bond station. This avoidsduplication of energy devices and exposure of such devices to thevarious machining processes. FIG. 25 schematically illustrates an energydevice 280 that slides up into a pocket in a support body 282. FIG. 26schematically illustrates an energy device 290 received into an end of asupport body 292. FIG. 27 schematically illustrates a flexible adhesivecuring device 300 mounted in a support body 302, parallel to thecontoured surface. The flexible curing device may be optical, thermal,induction coil, piezo or through atomic excitation of the adhesivemolecules by coupling with nano components present in the workholdingadhesive.

In an alternative workholding system, the workpiece shuttle may take theform of individual gripping devices that cooperate to hold theworkpiece. FIG. 28 provides a perspective view of an alternativeembodiment of a gripping device, such as a transparent component 310,which would cooperate with a similar component 312 to support aworkpiece 202 as shown in FIG. 29 . Because the working area of theworkpiece is at each end of the part it is not necessary to support theworkpiece in the middle area. Once the workpiece is assembled byadhering the two individual gripping devices it can be referred to agripping assembly or workpiece shuttle. The accurate positioning of thegripping devices is performed by the use of a bond station. Thecomponents 310 and 312 may have integral workpiece locating elements,314, that accurately position the workpiece relative to the componentsand to a bond station. In an example, the components have contouredsurfaces 318 that are complementary to corresponding areas on theworkpiece 202, and the entirety of the contoured surface may be formedof transparent material to allow UV curing through the componentsurfaces. In this example, the bonding zone includes one zone for eachcomponent, where the component surface is coextensive with the workpiecesurface. Energy devices may be received as shown in FIGS. 25-27 .

FIG. 30 provides a perspective view of an alternative embodiment of aportion of a workpiece shuttle with a turbine blade element similar toFIG. 29 but with a tie-bar 320 spanning two transparent locatingcomponents 310 and 312. Because the working area of the workpiece is ateach end of the part it is not necessary to support the workpiece in themiddle area. Once the workpiece is assembled by adhering the twoindividual gripping devices it can be referred to a gripping assembly294. The accurate positioning of the gripping devices is performed bythe use of a bond station, similar to that shown in FIG. 20 . Thetie-bar assembly provides for a means to attach a zero point locatingsystem such as the one depicted earlier.

FIG. 31 depicts an insertable curing device 330 which is inserted intopocket 332 of a component 310.

FIG. 32 provides a perspective view of a gripping device or component340 which incorporates slots 342 in a contoured surface and atransparent material in the slots to transmit ultraviolet light into anadhesive for attachment to the workpiece. FIG. 33 shows the grippingdevice 340 and an insertable LED device 344 which includes an LED array346 to provide the ultraviolet light.

Any of the herein described approaches to illuminating a bonding zonemay also be used with the embodiment shown in FIGS. 14-17 , such as byadding UV sources into the upper portion or providing upper UV sourcesto the bond station.

FIG. 34 shows a workholding system 350 comprised of a base 352, a zeropoint chucking device 354, adhesive curing devices 356, a workpieceshuttle 358, and the workpiece 202. 352, 354, are known collectively asa bond station. The zero point device is comprised of a locating andclamping system 354, 360 which accurately positions the shuttle 358 in aknown position. Once the adhesive is solidified and the workpieceassembly, comprised of workpiece 202 and shuttle 358, are attached toone another, the zero point clamp is released and the part is introducedinto the processing line. It is important to note that the entirebonding process, in this and other certain other embodiments, happensoutside of the machine cycle, significantly increasing the amount ofcompleted parts that can be processed in one day. Furthermore, the samezero point system used in the bond station may be used in multiplemachine tools allowing for simple loading of complex shaped workpiecesthrough the use of automation. The prior art of loading a complex shapedpart, such as a turbine blade element into a hard point clamping fixtureinside of a machine tool, is difficult and time consuming. Furthermore,by using the same zero point system inside an inspection machine, afurther reduction in processing time can be achieved. It should also benoted that by using the same zero point system throughout the productionline, multiple part numbers may take advantage of the already mountedzero point system that is in the processing chain by simply using aseparate bond station dedicated to a new part number.

FIG. 35 depicts a robot 370 loading a workpiece 202 onto a workpieceshuttle 372. It will also be noted that a robot may load a workpieceinto bond station/shuttle system.

FIG. 36 depicts a 6^(th) axis 388 to rotate the shuttle 210 withworkpiece 202 attached. This method provides a means to machine theentire workpiece.

FIG. 37 illustrates a conveyor system 380 with the adhesive curingsource 382 mounted below a conveyor 384. Element 386 is a transparentmaterial that allows ultraviolet light to be transmitted up through abond station and shuttle on the conveyor 384 to expose the workholdingadhesive to ultraviolet radiation to cure the adhesive. As part of theconveyor system 380, the conveyor belt 384 may have cutouts, as shown.Referring again to FIGS. 13 and 15 , the bond station 230 may haveopenings 239 in the lower face 232 to allow UV to pass from the curingsource to the shuttle 210. Likewise, the shuttle 210 may have openings224 to allow the UV to pass through to the transparent support body. Theversion of the shuttle shown in FIGS. 14-17 may also have openings 224for UV to pass through. The conveyor system may have an additional UVsource to illuminate the second support body 213.

FIG. 38 depicts a production system whereby unmounted workpieces areintroduced into the conveyor and mounted parts exit out the opposite endwhere the shuttles 210 and bond stations 230 are separated. Multiplepart numbers 387 may be put through the conveyor at a time supplyingmultiple work cells with product. With the use of an identificationsystem utilizing vision, laser, RFID, or other means, each part numbermay be placed into the corresponding manufacturing cells.

FIGS. 39 and 40 provide cross sectional side and top views of theconveyor system 380, conveyor 384, curing source 382, transparentmaterial 386 and a position sensor 388 for determining when to stop theconveyor belt.

The conveyor may take the form of a UV curing area without a transportmechanism. Instead, a bond station is positioned in the UV curing area,the area may be enclose, and the UV illumination occurs

FIG. 41 provides a schematic view of a system for machining a supportbody for use with certain embodiments of the present invention. Thisprovides a method to manufacture a transparent or semi-transparentceramic support 406 by means of an abrasive wire 402 guided by alignmentwheels 400 and manipulated in 2 rotary axes 404 and 2 linear axes 408.Another embodiment is to form a transparent material into a shape byadditively printing the material or forming it into a mold.

It is noted that the present invention is not limited to turbine bladeelements, though it is especially useful therewith. It may also be usedwith other workpieces where adhesive attachment is beneficial. Anyreference to a “turbine blade element” may be replaced with “workpiece”herein.

Referring now to FIG. 42 , a method in accordance with the presentinvention is illustrated. In one embodiment, the method is fortemporarily holding a turbine blade element during one or moremanufacturing processes. The turbine blade element has a central bladeportion and at least one end portion. The central blade portion has acontoured blade surface. In step 500, a workholding system is provided.The workholding system includes: a support body having a contoured bodysurface complementary to the contoured blade surface, the complementaryportion of the contoured body surface defining a bonding zone entirelyformed of a transparent material; a base attached to and supporting thesupport body so as to form a workpiece shuttle, the base having aplurality of zero-point locating elements configured to locate the baserelative to a manufacturing workstation; and a bond station configuredto receive the shuttle, the bond station having a plurality ofzero-point locating elements complementary to the zero-point locatingelements of the base, the bond station further having a plurality ofworkpiece locating elements. In step 502, the shuttle is received on thebond station. In step 504, the shuttle is positioned in a predefinedposition by the complementary zero-point locating elements of the baseand bond station. In step 506, a UV curable workholding adhesive isapplied to the bonding zone between the contoured blade surface and thecomplementary body surface In step 508, the turbine blade element isreceived on the support body with the contoured blade surface adjacentthe bonding zone. In step 510, the turbine blade element is positionedon the shuttle in a predetermined position relative to the zero-pointlocating elements of the base of the shuttle by the plurality ofworkpiece locating elements of the bond station. In step 512, theadhesive in the bonding zone is illuminated through the transparentmaterial, thereby curing the adhesive such that the turbine bladeelement is temporarily fixed in the predetermined position relative tothe zero-point locating elements of the base of the shuttle. In step514, the shuttle, with the turbine blade element affixed thereto, isremoved from the bond station and the shuttle and turbine blade elementare moved to a first manufacturing workstation. In step 516, at leastone manufacturing process is performed. In step 518, the turbine bladeelement is de-bonded from the shuttle. In some embodiments, the stepsare performed in this order. In other embodiments, some steps may beperformed in other orders. For example, the adhesive may be appliedearlier.

What is claimed is:
 1. A method for temporarily holding a turbine bladeelement during one or more manufacturing processes, the turbine bladeelement having a central blade portion and at least one end portion, thecentral blade portion having a contoured blade surface, the methodcomprising: providing a workholding system having; a support body havinga contoured body surface complementary to the contoured blade surface,the support body entirely formed of a transparent material and anentirety of the contoured upper body surface is formed of thetransparent material and defines a bonding zone; a base attached to andsupporting the support body so as to form a workpiece shuttle, the basehaving a plurality of zero-point locating elements configured to locatethe base relative to a manufacturing workstation, the base furtherhaving a support face; and a bond station configured to receive theshuttle, the bond station having a plurality of zero-point locatingelements complementary to the zero-point locating elements of the base,the bond station further having a plurality of workpiece locatingelements; receiving the shuttle on the bond station, wherein the supportbody is interconnected with the base to form the shuttle prior to thereceiving step; positioning the shuttle in a predefined position by thecomplementary zero-point locating elements of the base and bond station;receiving the turbine blade element on the support body with thecontoured blade surface adjacent the bonding zone; positioning theturbine blade element on the shuttle in a predetermined positionrelative to the zero-point locating elements of the base of the shuttleby the plurality of workpiece locating elements of the bond station;applying a UV curable workholding adhesive to the bonding zone betweenthe contoured blade surface and the complementary body surface;illuminating the adhesive in the bonding zone through the transparentmaterial with UV, thereby curing the adhesive such that the turbineblade element is temporarily fixed in the predetermined positionrelative to the zero-point locating elements of the base of the shuttle;removing the shuttle, with the turbine blade element affixed thereto,from the bond station and moving the shuttle and turbine blade elementto a first manufacturing workstation; performing at least onemanufacturing process; and debonding the turbine blade element fromsupport body of the shuttle without disassembly of the support body fromthe base of the shuttle.
 2. The method of claim 1, wherein the step ofilluminating the adhesive comprises: providing a UV curing stationhaving a UV light source; disposing the bond station, with the shuttleand turbine blade element thereon, in the UV curing station; andilluminating the adhesive using the UV curing station.
 3. The method ofclaim 2, wherein: the UV curing station comprises a UV conveyor having aUV light source and a conveying element; the step of disposing the bondstation, with the shuttle and turbine blade element thereon, in the UVcuring station comprising disposing the bond station, with the shuttleand turbine blade element thereon, on the conveying element; and movingthe bond station, with the shuttle and turbine blade element thereon,relative to the UV light source by the conveying element.
 4. The methodof claim 3, wherein: the conveying element is disposed above the UVlight source such that the conveying element moves the bond station overthe UV light source; and UV light from the UV light source passesupwardly through one or more openings in the shuttle and bond station soas to illuminate the bonding zone.
 5. The method of claim 1, wherein theworkpiece shuttle further comprising a UV light source disposed in oradjacent to the transparent material and configured to illuminate thebonding zone.
 6. The method according to claim 1, wherein the step ofilluminating the adhesive comprises: providing a UV light sourcedisposed in the workpiece shuttle; and illuminating the adhesive usingthe UV light source.
 7. The method according to claim 1, wherein theworkpiece shuttle further comprises an upper portion with a secondsupport body, the second support body having a contoured body surfacecomplementary to an additional contoured blade surface of the turbineblade, an additional bonding zone defined where the contoured bodysurface of the second support body is coextensive with the additionalcontoured blade surface, the method further comprising moving the upperportion of the workpiece shuttle from an open position to a closedposition wherein the contoured body surface of the second support bodyis adjacent the additional contoured blade surface.
 8. The methodaccording to claim 7, further comprising applying the adhesive to theadditional bonding zone, the illuminating step comprising illuminatingthe adhesive in both bonding zones.
 9. The method according to claim 7,wherein: at least a portion of the contoured body surface of the secondsupport body is formed of a transparent material; or the second supportbody is entirely formed of the transparent material.
 10. A method fortemporarily holding a workpiece during one or more manufacturingprocesses, the workpiece having a contoured surface, the methodcomprising: providing a workholding system having; a support body havinga contoured body surface complementary to the contoured surface of theworkpiece, the support body entirely formed of a transparent materialand an entirety of the contoured upper body surface is formed of thetransparent material and defines a bonding zone; a base attached to andsupporting the support body so as to form a workpiece shuttle, the basehaving a plurality of zero-point locating elements configured to locatethe base relative to a manufacturing workstation, the base furtherhaving a support face; a bond station configured to receive the shuttle,the bond station having a plurality of zero-point locating elementscomplementary to the zero-point locating elements of the base, the bondstation further having a plurality of workpiece locating elements;receiving the shuttle on the bond station, wherein the support body isinterconnected with the base to form the shuttle prior to the receivingstep; positioning the shuttle in a predefined position by thecomplementary zero-point locating elements of the base and bond station;receiving the workpiece on the support body with the contoured surfaceadjacent the bonding zone; positioning the workpiece on the shuttle in apredetermined position relative to the zero-point locating elements ofthe base of the shuttle by the plurality of workpiece locating elementsof the bond station; applying a UV curable workholding adhesive to thebonding zone between the contoured surface of the workpiece and thecomplementary body surface; illuminating the adhesive in the bondingzone through the transparent material with UV, thereby curing theadhesive such that the workpiece is temporarily fixed in thepredetermined position relative to the zero-point locating elements ofthe base of the shuttle; removing the shuttle, with the workpieceaffixed thereto, from the bond station and moving the shuttle andworkpiece to a first manufacturing workstation; performing at least onemanufacturing process; and debonding the workpiece from the support bodyof the shuttle without disassembly of the support body from the base ofthe shuttle.
 11. The method according to claim 10, wherein: theworkpiece shuttle further comprises an upper portion with a secondsupport body, the second support body having a contoured body surfacecomplementary to an additional contoured surface of the workpiece, anadditional bonding zone defined where the contoured body surface of thesecond support body is coextensive with the additional contoured surfaceof the workpiece; the method further comprising moving the upper portionof the workpiece shuttle from an open position to a closed positionwherein the contoured body surface of the second support body isadjacent the additional contoured surface of the workpiece; the step ofapplying adhesive comprising applying adhesive to both bonding zones;and the step of illuminating comprising illuminating the adhesive inboth bonding zones with UV.
 12. The method according to claim 10,wherein the step of illuminating the adhesive comprises: providing a UVcuring station having a UV light source, the UV curing station having aUV light source and a conveying element, the conveying element disposedabove the UV light source such that the conveying element moves the bondstation over the UV light source; disposing the bond station, with theworkpiece shuttle and workpiece thereon, in the UV curing station; andilluminating the adhesive using the UV curing station, the UV light fromthe UV light source passing upwardly through one or more openings in theworkpiece shuttle and bond station so as to illuminate the bonding zone.13. The method of claim 1, wherein the support body is a monolithic bodyof the transparent material.
 14. The method of claim 1, wherein thecontoured body surface of the support body is a non-flat surface. 15.The method of claim 1, wherein the contoured body surface bonding zoneis the entirety of the coextensive area.
 16. The method of claim 1,wherein the debonding step comprises debonding with hot water or hotair.
 17. A method for temporarily holding a workpiece during one or moremanufacturing processes, the workpiece having a contoured surface, themethod comprising: providing a workholding system having; a support bodyhaving a contoured body surface complementary to the contoured surfaceof the workpiece, at least a portion of the contoured upper body surfaceformed of the transparent material and defining a bonding zone; a UVlight source disposed in the support body such that the UV light sourceis operable to provide UV illumination through the transparent material;a base attached to and supporting the support body so as to form aworkpiece shuttle, the base having a plurality of zero-point locatingelements configured to locate the base relative to a manufacturingworkstation, the base further having a support face; a bond stationconfigured to receive the shuttle, the bond station having a pluralityof zero-point locating elements complementary to the zero-point locatingelements of the base, the bond station further having a plurality ofworkpiece locating elements; receiving the shuttle on the bond station,wherein the support body is interconnected with the base to form theshuttle prior to the receiving step; positioning the shuttle in apredefined position by the complementary zero-point locating elements ofthe base and bond station; receiving the workpiece on the support bodywith the contoured surface adjacent the bonding zone; positioning theworkpiece on the shuttle in a predetermined position relative to thezero-point locating elements of the base of the shuttle by the pluralityof workpiece locating elements of the bond station; applying a UVcurable workholding adhesive to the bonding zone between the contouredsurface of the workpiece and the complementary body surface;illuminating the adhesive in the bonding zone through the transparentmaterial with the UV light source, thereby curing the adhesive such thatthe workpiece is temporarily fixed in the predetermined positionrelative to the zero-point locating elements of the base of the shuttle;removing the shuttle, with the workpiece affixed thereto, from the bondstation and moving the shuttle and workpiece to a first manufacturingworkstation; performing at least one manufacturing process; anddebonding the workpiece from the support body of the shuttle withoutdisassembly of the support body from the base of the shuttle.
 18. Themethod of claim 17, wherein the support body has a pocket definedtherein and the UV light source is inserted into the pocket.
 19. Themethod of claim 18, wherein the support body comprises a componenthaving a metal body with openings, the openings having the transparentmaterial disposed therein.